With the continuous progress of technology and science, the demand for electronic devices by general consumers is increasingly upgraded, especially for consumer electronic products. Electronic devices, which were bulky in size, such as optic disk players, household telephones, and desk-top computers, are being changed to compact and portable electronic products of high performance, such as multimedia player (for example MPEG Audio Layer-3, MP3), mobile phones, and notebook computers, all leading to a more efficient life for human beings.
Most of such portable electronic products, including the multimedia players and mobile phones, are powered by rechargeable batteries or cells, such as nickel hydride battery and lithium battery. The rechargeable battery is re-chargeable through a charging device or charger, which is composed of a charging seat and an electrical connector. The charging seat forms a charging chamber in which the rechargeable battery is positioned, while the electrical connector is set in connection with a power socket, such as a wall outlet to supply a required voltage or current to charge the rechargeable battery. On the other hand, the electronic device, such as notebook computer, is provided with an adaptor that is electrically connectable with the wall outlet, whereby the adaptor that receives electrical power from the wall outlet supplies a required voltage or current to the notebook computer. Since the portable electronic products must be powered through the adaptor or by a rechargeable battery, those who attempt to carry these products outdoors must also carry various adaptors or chargers. This is very inconvenient for the users of the products and makes the use inconvenient. Further, the charging device or the adaptor must use connection wires to transmit electrical power for charging the rechargeable battery. This limits the range where the charging device or the adaptor is useful.
To overcome the above discussed problem, a wireless charging device was proposed, which comprises a wireless circuit formed on a surface of the wireless charging device to receive a portable electronic product to be placed thereon for charging. The wireless charging device has an opposite surface on which a magnetic conduction plate or a magnetic shield plate is mounted to prevent magnetic leakage from interfering with or affecting surrounding metal articles or other articles. However, since the wireless charging device comprises the wireless circuit on only one surface thereof with the opposite surface being provided with a magnetic conduction plate or a magnetic shield plate, charging operation can only be performed on said one surface.
Thus, the present invention aims to provide more convenience to the user by providing a double-sided bidirectional wireless power device that has increased surface areas for charging and discharging which allows for the simultaneous wireless power transfer of up to two electrical devices.